Method for controlling the spangling of galvanized sheets



H. E. M COY 2,086,278

METHOD FOR CONTROLLING THE SPANGLING OF GALVANIZED SHEETS July 6, 1937;

, Filed May 14, 1934 5 Sheets-Sheet l INVENTOR' Harry 5 MC C0] BY *T I 4; ATTORNEY$ H. E. M COY 2,086,278

METHOD FOR CONTROLLING THE SPANGLING OF GALVANIZED SHEETS July 6, 1937.

Filed May 14, 1934 3 Sheets-Sheet 2 Harry KMCCO} INYENTOR 4M ATTO RN EYS July 6,- 1937. H. E. MCCOY 2,086,278

METHOD FOR CONTROLLING THE SPANGLING OF GALVANIZED SHEETS Filed May 14, 1954 5 sneets-sheet s HG/Ij 5 MC Coy 3nventor Gttorneg;

Patented July 6, 1937 UNITED STATES PATENT OFFICE METHOD FOR CONTROLLING THE SPAN- GLING OF GALVANIZED SHEETS Jersey Application May 14, 1934, Serial No. 725,586

2 Claims. (Cl. 91-702) My invention relates to a'novel method for controlling the productio'n of spangles on galvanized sheets to produce a more uniform distribution of the spangles over the sheet and to obtain as a result a sheet of more attractive appearance than that of the galvanized sheets now on the market. v

Heretofore the practice has been to pass sheets from the spelter bath onto a table, rolls or suitable conveyor where the spelter coating is allowed to chill and cool and the spangles to form ad libitum and without any means being provided, or steps being taken, to control the distribution of the spangles over the sheet.

In accordance with my invention I provide a pair of duplicate spangling rolls geared together and provided with teeth so arranged and matched that they will produce on both sides of n the sheet as it passes between them opposed contacts on predetermined closely associated centers both transversely and longitudinally of the sheet, which centers determine the foci for the spangles that occur as a result of crystallization of the spelter coating.

My process contemplates that these spangling rolls shall be so positioned with relation to the sheet after its emergence from the spelter bath :that the spangle controlling teeth, when they contact the sheet, will do so at the time when crystallization is ready to take place in the coating and where the chilling efiect of the opposing teeth contacting the plate between them will act to localize the foci of crystallization without disturbing the effective amalgamation of the spelter coating with the metal sheet. This position will have to be determined empirically, but when the spangling rolls are properly set and the temperature of the spelter bath maintained uniform, the practice of my novel method will produce sheets having controlled substantially uniformly distributed spangles on both sides of the sheet, which gives a sheet a far more attractive and ornamental appearance than where the spangles are allowed to occur haphazard, or as the result' 45 of contact of the conveyor rolls or otherwise,

throughout the sheet.

My process results in the production of relatively smaller spangles like flowers or leaf clusters which are closely associated and produce a coated sheet having a less tendency for its coating material to flake ofi than is the case of ordinary galvanized sheets which have the larger uncontrolled spangles.

My invention further contemplates conducting the sheets to the spangling rolls over toothed rollers which will exert the least possible disturbance on the chilling spelter coat and will not themselves exert any control of the spangling but will act to support the sheet clear of the rolls so that it will cool and eventually chill its coating on both sides as it approaches the spangling rolls.

If desired the teeth on the carrier rolls ahead of the spangling rolls can have an arrangement corresponding to that of the teeth on the lower spangling roll and can be geared thereto so that their contact points on the sheet will register with each other and with the contact points for the teeth on the lower spangling roll so that there will result no disturbance of the contemplated arrangement of crystallization foci on the underside of the sheet by reason of its contact with the carrier rolls.

The preferred manner of practicing my invention will be better understood by reference to the apparatus which I have found suited to that end and which is illustrated in the accompanying drawings in its preferred embodiment only.

In the drawings:-

Fig. l is a plan view of the machine with the spelter bath broken away and the sheet under treatment. omitted.

Fig. 2 is a cross sectional view taken on the broken line 11-11 of Fig. 1.

Fig. 3 is a sectional view taken on the linev III-III of Fig. 1, showing the sheet being engaged by the spangling rolls.

Fig. 4 is a detail view broken away of the spangling rolls and their driving gears.

Fig. 5 is a view of a galvanized sheet produced by my process with lines drawn on one inch centers corresponding to the spacing of the spangling teeth so that their points of intersection indicate the contact points of the spangling teeth and show in an illustrative way vhow the spangling roll teeth control the distribution of the spangles.

Similar reference numerals refer to similar parts throughout the drawings.

In the embodiment of my invention illustrated in the accompanying drawings, I show as a suitable apparatus for carrying my method into effeet a tank 5 containing a bath of molten spelter, zinc or other metal capable of forming a protective coating on metal sheets and which as it cools .will crystallize and form spangles or the like.

I indicate the spelter bath at 6 and show a metal sheet '1 emerging from the bath propelled by means of any suitable conveyor or carrier means not necessary to be shown and passing upwardly between a pair of smooth stripping rolls 8 which tend to remove the excess of spelter from both sides of the sheet.

From the rolls 8 the sheet passes upwardly into engagement with the curved center guide 9 which directs it to the right over the initial toothed roller II] that is suitably journaled in a bed frame 1 II. The sheet passes from this roll l0 over a second toothed roll l2, also suitably journaled on the frame, into the pass between the pair of toothed spanglingrolls l3 from which it emerges in position to be received upon conveyor chains ll having suitable driving sprockets l5 which deliver the sheets to the inspection table or other desired point of handling.

The rolls l and I! have their shafts journaled in boxes l6 which are laterally adjustable by means of screws I! in their respective housing is. The bed frame carries a vertical extension frame l9 which receives the journal boxes 20 for the shafts of the spangling rolls I3, which shafts at their front ends extend beyond their bearings and receive gears H which mesh and drive the mils in unison with their respective teeth in opposed relation at the moment of their contact with the interposed sheet I.

The working faces of the spangling rolls, and also of the rolls l0 and i2, are provided with teeth 22 preferably of the frusto-pyramidical type spaced on close centers. Excellent results in the spangling rolls have been obtained from teeth, with tips about %"'square and bases V square, set approximately on one inch centers both axially and circumferentially of? the roll. The above dimensions are given for illustrative purposes only and do not limit the invention to any particular design or arrangement of the spangle controlling teeth.

It will be observed from Fig. 3 that the spangling rolls are geared and set so that their teeth 22 will align at the point of contact with the metal plate 1. If desired, similar teeth may be used on the rolls l0 and I2, and all of the rolls may be driven from the power shaft 23 through a sprocket 26, chain 25 to a sprocket 26 on the shaft of roll l0, thence by a second sprocket 27 and chain 28 to a sprocket 29 on the shaft of roll l2, and thence by a sprocket 30 and chain 3! to a sprocket 32 on the shaft of the lower spangling roll l3 which, through the gears 2i, drives the upper spangling roll. The power shaft 23 is mounted in bearings 33 and drives the conveyor sprockets l5, and through the meshing gears 2i drives the upper spangling roll. The rolls are thus all driven together and their kept in step, with the teeth on rolls l0 and I2 set to contact the sheet if desired at the same points that the teeth on spangle rolls will contact it.

A blow pipe 34 is provided and disposed to direct a blast-across the coated sheet to cool or treat it.

The opposing teeth on the spangle rolls make firm and definite contact with the sheet 7 and this contact serves, either by a chilling of the coating at that point oi otherwise, to localize and spot the foci of crystallization with the result that the spangles are caused to form with almost complete uniformity on inch centers over the sheet, whereby I obtain a regular and controlled distribution of the spangles which appear smaller and of a more uniform size and shape than in the case of uncontrolled spangles. These small spangles have the appearance of flowers or leaf clusters with the petals or leaves radiating from the crystallization'foci and producing a resultant sheet that has an intricate, attractive and more uniform surface ornamentation by reason ofthe controlled arrangement of its spangles.

In Fig. is shown a photographic reproduction from a sheet of galvanized metal that has had my controlled spangling treatment with the intersecting lines approximately on inch centers and their intersections represent the points of teeth can be contact of the spangling teeth.- With only negligible exception the foci of crystallization, representing the centers of the spangles, coincide with these contact points of the teeth of the spangling rolls. 5

It will be understood that the spangling rolls are capable of relative adjustment to accommodate different thicknesses of sheets so that their teeth will definitely contact the sheets as they pass between them. Further, these spangling rolls are set with relation to the bath so that the sheet when it reaches them has cooled to' the point that its spelter coat is ready for the crystallization process to commence and is therefore ready to respond to the chilling contact of the i5 spangling teeth so as to set up the crystallization l about the point of contact asa center and thus to produce the controlled arrangement of the spangles. Neither the spangling rolls nor the carrier rolls that precede them are chilled but operate at the temperature they will naturally attain as a result of constant contact with the hot sheets. Their teeth will naturally have a lower temperature than the coating on the sheets but, not being artificially chilled nor prematurely brought into contact with the coating, they will not disturb its amalgamation with the metal sheets. The spangling rolls themselves should be so spaced from the spelter tank that they a will not contact a sheet until its coating is on the point of crystallization and, since the amalgamation of the coating with the sheet will be completed by the time the coating is ready for natural crystallization into spangles, it follows that my spangling rolls will not disturb or adversely afiect the amalgamation but yet will be effective, by the contact of their teeth with the chilling spelter coating, to control the spangling by localizing its foci of crystallization.

While I have shown myinvention in but one 40 form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications, without departing from the spirit thereof, and I'desire,

therefore, that only such limitations shall be the sheet and reached the temperature where its 5 crystallization will naturally occur, and then subjecting the sheet to the action of unchilled spangling rolls which by multiple point contact therewith will control and localize the foci of k crystallization that form the spangles.

2. The herein described method for controlling the spangling of sheets coated with spelter and the like, which consists in immersing the sheet in a molten bath of coating, conveying the sheet from the bath until the amalgamation of the coating with the sheet has been accomplished and crystallization of the coating is ready to occur naturally, and at that time subjecting the sheet to contact with relatively cooler spangling control points for controlling the localization of the foci of crystallization and effecting a controlled arrangement of the spangles.

HARRY I. my. 

